Chassis Setup Trends - The Evolution Of Stock Car Setups

For eight years now we have presented, examined, dissected, and rejected most of the setup trends racers are using today. Not much has passed us by because of the contacts we have and the large number of racers I personally talk to on a day to day basis. What follows is a synopsis of the evolution of setups for dirt and asphalt over that period of the past 20 years.

2/13Part of the transition in setup technology over the past 20 years was heavily influenced by directions engineers in Cup took. Was that good or bad for short track racers? We shall see.

What is important about this overview is that we can see a pattern emerge of how unfortunately many, and maybe most, racers are followers and hold to the age old principle that the grass is always greener on the other side of the pits. Unfortunately nothing could be further from the truth.

I have had a 20-year career working directly with race teams. I can tell you that I've been disappointed more times than pleased with the direction the teams go after, and sometimes while, I am coaching them. It's as if they can't maintain a direction and follow through with a plan.

The first rule of success is that if you keep doing what you've always done, you will always get the same results. Those are not my words, I forget the author right now, but there is a ton of truth in that statement. If you keep making changes to your setup based on nothing more than a whim, then you will continually be off balance, excuse the pun, with your setups. And success will never come.

I'm a firm believer in choosing a path, learning all you can about that path, and then go full steam ahead with the journey. It's the way I've lived my whole life. And you can live that way too. If you really want to run a Big Bar and Soft Spring setup or tie down the front of your Dirt Late Model with 2,500 pounds of rebound at 3 inches per second, then do it, and do it all the way, not that I in any way approve.

3/13One of the important technologies that arrived during the '90s was a better understanding and methods of application of the geometry of the race cars. For once, the true dynamics that affected the handling and performance of race cars through the design of the suspensions and the setups could be understood and manipulated for ultimate performance.

If you get the point, then let's proceed and maybe we can find a path for you. Think back on the things you have done setup wise over the years, however many that is for you, and try to evaluate how you've conducted yourselves in the evolution of your setups.

Circa 1995
It was during the early to middle '90s that I went full-time with race car engineering. What I did first was try to evaluate and learn the state-of-the-art in chassis engineering. I read all of the current best sellers including a book that was popular with the Cup teams at that time, Race Car Vehicle Dynamics by the Milliken brothers.

What soon became apparent was that information was plentiful on various subjects such as geometry, dynamics, aerodynamics and mechanics. In all of that, I never could find an author who put all of that together into a package and said, here is how you find your perfect setup. No one could offer a plan, or path, upon which to build a setup the car wanted.

4/13Methods for making changes to the geometry for improved control of the forces acting on the race car were explained in Circle Track and the response from the teams and car builders was extremely positive.

So, that is where I began, with little useful information on which to build. When there's no pattern or set of plans, we must improvise or design for ourselves. It ends up being a trial and error process and I've said before that I hate trial and error.

I learned that even in Cup racing at that time, all of the teams tried this and that and mostly played follow the leader, or faster car, in the way they setup their cars. Even in short track racing in certain regions, teams just did what the winners did, or more correctly what they thought the winners were doing.

Most race cars then were setup up tight. That was to say they didn't turn well, abused the right front tire, and ended up with a severe push or went tight/loose eventually. Even at Daytona, Cup cars were setup tight to where the right front carried most of the front load and so we saw what were referred to as freight train springs upwards of 2,400 ppi rates.

Top asphalt teams in the Midwest ran softer right rear springs at all of the tracks, even very high banked ones where it was ridiculous to do so. But everyone did it, so no one was aware that there could be a different way.

5/13Once the teams understood the methodology for making the suspension system designs better, they then went to their race cars and made the necessary changes, even if that meant cutting up and re-positioning the attachment points for the control arms.

Dirt Late Model teams ran not only softer right rear springs, but very stiff front springs to boot. Yes, they needed good bite off the corners on dry slick, but having to park the car in the middle because it wouldn't turn the corner made that necessary.

And the most significant trend that permeated the industry was the pursuit of the fastest lap time. Almost to a team, 100 percent, every driver would go out in short runs and experiment with different spring combinations trying to lay down that fast lap.

In the shorter races, this could be successful, but for longer events, it was a disaster. What was needed was a better understanding of the dynamics and physics of our race cars. And things were soon to change for the better.

Late '90s To Early '00S
In the late '90s, a select few teams started experimenting with what we have called creating a balanced setup. Balance is not only having a neutral handling car, but a system of spring rates and moment (roll) centers whereby the front and rear suspension systems are working in unison, not against each other.

6/13The Dirt Late Model, as are many classes of dirt cars, is a complicated design with a multitude of variables. Not only are the dynamics important to understand and design for, but the various settings for alignment and dynamic wheel steer make finding the best set of conditions very difficult. What we found was that the simpler we made the setup and geometry settings, the better the car was over a longer period of time.

What we saw with these teams was an immediate improvement in driveability, prolonged speed (i.e. the lap times did not fall of as much), better tire wear, and cars that were more capable of winning a race.

This happened across the board with Cup teams and short track asphalt teams in the Midwest, Northeast, Southeast, and West Coast. How do I know that? Because I was in communication with teams that had transitioned into that path and it was paying off big time.

In Dirt Late Model, a few teams experimented with running even springs across the rear and lowering the front spring rates, against the advice of the car builders, some of whom were understandably irate. Then, during Speedweeks, sometime around 2002, Don O'Neal ran a stiffer right rear spring at East Bay's Winternationals and then again at Volusia and won consistently.

In conjunction with the transition in spring rates, teams were fooling around with their front geometries and finding that locating the moment center in a certain area helped the front to gain grip and to help turn the car. Now we were getting somewhere.

7/13Through the '90s, setups evolved to where the teams ran softer front springs combined with stiffer rear springs, especially the right rear. Those changes combined with a better design for front end geometry meant that they were now racing on all four tires for once.

Asphalt teams were doing much the same thing and in the Midwest, the team of Brian Hoppe completely bucked the system with its setups in 1998 and finally won the Re/Max Challenge Series, after finishing Second twice, in a classic battle with Steve Carlson.

In the Southeast, the father and sons team of Jim, Jon, and Jeff Craig made changes that balanced their Goody's Dash car and won four races in a row going on to win not only the championship in that former division of NASCAR, but the Late Model touring division numerous times later on.

Out west, Craig Raudman, founder of Victory Circle race cars, won the NASCAR touring division there with this new concept. And I began writing for CT in 1998 with much the same message for the readership. I saw car builders who were curious as to why certain teams running their cars were winning on a consistent basis.

The design of both asphalt and dirt cars was influenced by what the racers were doing outside the manufacturers "playbook." It pissed off some of the car builders and woke up some others. The smart ones realized that if a new technology could help their cars win, sales would increase, it had always worked that way. And they did.

Things were looking good for common sense setups where the car was happy; the tires were happy; and the driver, team, and car owners were happy. But just like America today, a good thing can be corrupted and soon "evil forces" began to manipulate the way teams setup their cars.

Mid To Late '00s
In what we can now call the modern era of stock car racing, we see a gradual change associated with the way setups are developed and the goals associated with development of the asphalt setups. I'll get to the dirt setups in a minute.

8/13Aero experimentation is not new to the '00s, this photo was taken circa 1974 and shows Jack Cook at New Smyrna Speedway with a wedge nose and large "whale tale" rear wing. With few body rules in place, the racers took to experimentation that was fun to watch.

What happened, I think, is that a small percentage of teams were truly working the balanced setup deal and they were dominating. When other teams could not find out how that was happening, or were technically challenged and couldn't figure it out for themselves, it became easier to bolt on parts to try to go fast.

So, we saw in Cup, as a direct result of the aero engineers taking over the lead in developing setups for those teams, where the teams made all of the setup decisions based on improving the aero efficiency of the cars and damned be the handling. The drivers would just have to adapt. It was a tough road, but one every team pursued because, hey, they were all doing it. Nice logic.

The problem was, too many short track teams paid attention to what the Cup teams were doing and began to copy them. Before you know it, we saw large sway bars, stiffer right rear springs, and body shapes that would produce more aero downforce at the front.

Now the teams that couldn't decipher how to create a balanced setup before merely had to bolt on parts and hit the track to go fast. The problem with that involves several areas of science.

9/13In many of our projects, we chose to run more conventional setups where the major issues concerning the setups were pre-designed to work together. The cars all performed well and we were able to demonstrate that those goals could lead to success. Many teams emulated those processes and reported their success back to us.

When you radically change the mechanics of the suspension in this way, you lose control of the fine tuning. It was soon discovered in all asphalt divisions including Cup, that finding the handling balance (forget the dynamic balance, it just ain't there anymore) was like walking on a knife edge. It was hard to find and harder to maintain.

It has been a frustrating five years or so for many teams. If you look at the fast times recorded at many racetracks over a 10-year period, the current trends have not improved those lap times, and in many cases have digressed over the long haul.

What we now see is a full circle trip back to the early '90s where, as we stated early on in this discussion, teams sought out the fastest lap time and disregarded the pursuit of longevity, or the goal of being fast at the end of the race, where it counts.

I witnessed this phenomenon at Lanier Speedway, the very first race event on our AMSOIL Great American CT Tour. The team that set fast time and led the first 25-30 laps was a good 2 to 3 tenths faster than the car running third. About 20 laps later, they traded places. The jackrabbit "start fast" car faded badly to third and the consistent car won. It was evident to my trained eye in the way the cars looked on the track that the balanced setup had beaten the BBSS setup. I rest my case.

10/13The late '00s goal of achieving a zero roll angle, low and flat configuration in the turns is unreasonable. To do this, the team needs to go against many of the basic principles that help a car to be fast and consistent. The result of deviation from those principles is a setup that is very difficult to make fast and harder to keep consistent.

As for the dirt guys, this setup thing gets really interesting. Most of the car builders have been influenced by what the teams have done through the early '00s with improvements to their front end geometry and moment center design as well as the arrangement of spring rates.

We saw front runners starting to keep the left front on the track, a more level attitude, less rear steer, and a more straight ahead driving style when track conditions permitted. But time marches on. As of this writing we see a trend in development that I hope dies soon.

It follows the line of thinking we saw with the asphalt guys and the BBSS setups. It involves using high rebound front shocks and very stiff right rear springs. Hey, sway bars aren't used in Dirt Late Model cars...yet, so stiff rebound shocks will have to do.

Is the BBSS mentality taking over Dirt Late Model racing? Not necessarily. Read my Tour review in this issue (page 48) and you'll learn about probably the most successful Dirt Late Model team in 2010 and I can assure you that it doesn't prescribe to the trend alluded to above.

What The Future Has In Store
Now that we have this overview, and admittedly it's my personal account and others may differ on the exact progression, we need to look at where all of this is going and where it will end up.

11/13We saw many new devices that were designed and implemented over the past 20 years, some of which made a significant improvement in handling and acceleration, and some which proved to be un-usable. Experimentation is the driving force for a race team most of the time.

I purposely left out of my account of the past 20 years of setup development the various tricks and gadgets companies and teams have come up with as to different designs of lift arms, pull bars, trailing arms, traction control, and rear steer. The decision to continue to use those and to what degree usually works out on its own.

Here are my thoughts on where all of this will end up. It's more a wish than anything else, but then I have always been an optimist at heart. I truly believe in the common sense of the average racer. And doesn't all of this really come down to basic common sense?

As for the dirt teams, a good look at the success some of the teams have had this year and how their setups look will tell most of the experimenters that exotic is not the way to go on dirt. Consistency means having a suspension that actually works and is not bound up by shocks or rear steer or overly stiff right rear springs.

12/13Parts for the race cars were improved through a natural process of experimentation and science. Endurance has been improved so that parts last longer and efficiency has been increased so that it takes less power to turn our transmissions and rearends.

They will find that in most cases, a balanced setup with correct front end geometry including the moment center location, will out run and out last any radical deviation from that. They might want to change their driving style to help reduce driver errors and to maintain momentum that will take them to the checkered flag.

The asphalt teams will need to back off on the big bars to a more reasonable size. They will need to get off the bump rubbers and coil binding and get back to running on a suspension like race cars are supposed to do, not like a kart.

There needs to be a moving away from the obsession with aero efficiency. On a half-mile or shorter track, aero ain't that big a deal. The teams who had to use aero to help turn the car through the middle never had their front end geometry sorted out in the first place.

13/13The concept of "balance" as it applies to the relationship between the front and rear suspension systems has been explained in CT many times over the past eight years. That concept has gained acceptance from industry leaders evidenced by the presentation of the same by Claude Rouelle in his seminars given around the globe.

On the hot and slick tracks in the summer months a return to a slightly softer right rear spring in conjunction with a balance between the two ends of the car will probably produce both faster lap times as well as the consistency to win.

What we need in racing, as well as in this country, is a return to a common sense approach to our methodology. It may sound too simple and you might think that all of this needs to be complicated, but it doesn't. Just follow the simple rules we have outlined in more than 100 articles over the past eight years and you will be successful. I promise.